Have you ever heard that there are times when the Sun appears to \u201cstand still\u201d right above your head? At that moment, if you stand outside, your shadow will disappear because sunlight shines directly down from above. This fascinating event is called <\/span>the Sun at its zenith<\/span><\/i> – one of the clearest pieces of evidence showing that the Earth moves around the Sun!<\/span><\/p>\n M\u1eb7t tr\u1eddi c\u00f3 th\u1eadt s\u1ef1 \u0111\u1ee9ng y\u00ean kh\u00f4ng?<\/b><\/p>\n Does the Sun really stand still?<\/b><\/p>\n Th\u1ef1c ra, m\u1eb7t tr\u1eddi kh\u00f4ng h\u1ec1 \u0111\u1ee9ng y\u00ean. Ch\u00ednh Tr\u00e1i \u0110\u1ea5t c\u1ee7a ch\u00fang ta \u0111ang nghi\u00eang v\u00e0 quay quanh M\u1eb7t Tr\u1eddi theo m\u1ed9t qu\u1ef9 \u0111\u1ea1o nh\u1ea5t \u0111\u1ecbnh. Khi v\u1ecb tr\u00ed c\u1ee7a Tr\u00e1i \u0110\u1ea5t khi\u1ebfn tia s\u00e1ng m\u1eb7t tr\u1eddi chi\u1ebfu vu\u00f4ng g\u00f3c v\u1edbi b\u1ec1 m\u1eb7t \u1edf m\u1ed9t khu v\u1ef1c n\u00e0o \u0111\u00f3, ng\u01b0\u1eddi ta n\u00f3i m\u1eb7t tr\u1eddi \u0111ang \u201cl\u00ean thi\u00ean \u0111\u1ec9nh\u201d t\u1ea1i n\u01a1i \u1ea5y.<\/span><\/p>\n Actually, the Sun doesn\u2019t stand still at all. It\u2019s our Earth that is tilted and revolves around the Sun in a specific orbit. When the position of the Earth causes the Sun\u2019s rays to shine perpendicular to the surface at a certain location, we say that the Sun is \u201cat its zenith\u201d there.<\/span><\/p>\n Hi\u1ec7n t\u01b0\u1ee3ng ch\u1ec9 x\u1ea3y ra \u1edf \u0111\u00e2u v\u00e0 khi n\u00e0o?<\/b><\/p>\n Where and when does this phenomenon occur?<\/b><\/p>\n Kh\u00f4ng ph\u1ea3i n\u01a1i n\u00e0o tr\u00ean Tr\u00e1i \u0110\u1ea5t c\u0169ng \u0111\u01b0\u1ee3c th\u1ea5y m\u1eb7t tr\u1eddi l\u00ean thi\u00ean \u0111\u1ec9nh \u0111\u00e2u nh\u00e9!<\/span> T\u1ea1i x\u00edch \u0111\u1ea1o, m\u1eb7t tr\u1eddi l\u00ean thi\u00ean \u0111\u1ec9nh hai l\u1ea7n m\u1ed7i n\u0103m (v\u00e0o kho\u1ea3ng 21\/3 v\u00e0 23\/9). \u1ede Vi\u1ec7t Nam, hi\u1ec7n t\u01b0\u1ee3ng n\u00e0y c\u0169ng di\u1ec5n ra m\u1ed9t \u0111\u1ebfn hai l\u1ea7n m\u1ed7i n\u0103m, t\u00f9y theo v\u0129 \u0111\u1ed9 t\u1eebng \u0111\u1ecba ph\u01b0\u01a1ng.<\/span><\/p>\n Not every place on Earth can witness the Sun at its zenith!<\/span><\/p>\n This phenomenon only happens between the two tropics \u2014 the area between the Tropic of Cancer (23.5\u00b0N) and the Tropic of Capricorn (23.5\u00b0S).<\/span><\/p>\n At the equator, the Sun reaches the zenith twice a year (around March 21 and September 23). In Vietnam, this event also occurs once or twice a year, depending on the latitude of each region.<\/span> Khi m\u1eb7t tr\u1eddi \u1edf thi\u00ean \u0111\u1ec9nh, c\u00f3 g\u00ec \u0111\u1eb7c bi\u1ec7t?<\/b><\/p>\n What\u2019s special when the Sun is at the zenith?<\/b><\/p>\n V\u00e0o th\u1eddi \u0111i\u1ec3m n\u00e0y, \u00e1nh n\u1eafng chi\u1ebfu g\u1ea7n nh\u01b0 th\u1eb3ng \u0111\u1ee9ng, khi\u1ebfn b\u00f3ng c\u1ee7a v\u1eadt th\u1ec3 g\u1ea7n nh\u01b0 bi\u1ebfn m\u1ea5t ho\u1eb7c r\u1ea5t ng\u1eafn. Nhi\u1ec7t \u0111\u1ed9 th\u01b0\u1eddng t\u0103ng cao h\u01a1n b\u00ecnh th\u01b0\u1eddng v\u00ec b\u1ee9c x\u1ea1 m\u1eb7t tr\u1eddi t\u1eadp trung m\u1ea1nh xu\u1ed1ng m\u1eb7t \u0111\u1ea5t. \u0110\u00e2y c\u0169ng l\u00e0 l\u00fac con ng\u01b0\u1eddi c\u1ea3m nh\u1eadn r\u00f5 nh\u1ea5t s\u1ee9c n\u00f3ng c\u1ee7a v\u00f9ng nhi\u1ec7t \u0111\u1edbi!<\/span><\/p>\n During this time, sunlight shines almost vertically, causing shadows to nearly disappear or become extremely short. The temperature also rises higher than usual because solar radiation is concentrated directly on the ground. This is when people can most clearly feel the intense heat of the tropics!<\/span><\/p>\n <\/p>\n M\u1ed9t ch\u00fat th\u00fa v\u1ecb v\u1ec1 chuy\u1ec3n \u0111\u1ed9ng c\u1ee7a Tr\u00e1i \u0110\u1ea5t<\/b><\/p>\n A fun fact about Earth\u2019s movement<\/b><\/p>\n Ch\u00ednh v\u00ec Tr\u00e1i \u0110\u1ea5t nghi\u00eang m\u1ed9t g\u00f3c 23,5\u00b0 so v\u1edbi m\u1eb7t ph\u1eb3ng qu\u1ef9 \u0111\u1ea1o m\u00e0 c\u00e1c n\u01a1i kh\u00e1c nhau tr\u00ean Tr\u00e1i \u0110\u1ea5t s\u1ebd l\u1ea7n l\u01b0\u1ee3t \u0111\u00f3n nh\u1eadn \u00e1nh s\u00e1ng m\u1eb7t tr\u1eddi theo g\u00f3c kh\u00e1c nhau trong n\u0103m. Nh\u1edd v\u1eady, ch\u00fang ta m\u1edbi c\u00f3 m\u00f9a n\u00f3ng \u2013 l\u1ea1nh kh\u00e1c nhau, v\u00e0 c\u00f3 c\u1ea3 hi\u1ec7n t\u01b0\u1ee3ng m\u1eb7t tr\u1eddi l\u00ean thi\u00ean \u0111\u1ec9nh n\u1eefa!<\/span><\/p>\n Because the Earth is tilted by 23.5\u00b0 relative to its orbital plane, different parts of the planet receive sunlight from varying angles throughout the year. That\u2019s why we experience changing seasons \u2014 and also why the phenomenon of the Sun at its zenith occurs!<\/span><\/p>\n![\"\"](\"https:\/\/i-clc.edu.vn\/wp-content\/uploads\/2025\/10\/MTLTD-4.jpg\")
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\n<\/span>Hi\u1ec7n t\u01b0\u1ee3ng n\u00e0y ch\u1ec9 x\u1ea3y ra gi\u1eefa hai ch\u00ed tuy\u1ebfn \u2013 t\u1ee9c l\u00e0 v\u00f9ng n\u1eb1m gi\u1eefa Ch\u00ed tuy\u1ebfn B\u1eafc (23,5\u00b0 B\u1eafc) v\u00e0 Ch\u00ed tuy\u1ebfn Nam (23,5\u00b0 Nam).<\/span><\/p>\n
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